I spent the weekend condensing and cloning my Win7 drive to a drive to Upgrade to Win10. It took about 14 hours to upgrade. Then I knew to avoid all AutoSpyware uploads to Microsoft and Disable all Express (we own your computer defaults) and Decline Cortana. Its done.. and boy is it an Ugly user interface.
I guess we will get use to it.. but seriously.. its Ugly. Dark Android 5 theme (which looks like Xfce or an old copy of CDE for Sun Microsystems) and very little user control. Lots of Ads and Lots of Upsell. -- I am so glad I have my original Win7 drive available. Its going to take some Numbing time to get used to this.
The good thing is by Upgrading and denying the Upload and Express settings.. my default Browser and other default app choices seem to remain in place. Irfanview, Video Lan Client, Media Player Classic, Print drivers. And (joy) I disabled Microsoft Edge successfully.. so succ-less.
The Start [thing] looks like an Xbox interface tilted on its side..
Un-pinning Store and All the Animated Tiles on the "Start-Xbox" menu calms down the Epileptic fits that menu invokes.